The following commit has been merged in the batman-adv/next branch: commit 42073d91a214587717c36a697436bad0f60c4384 Author: Alexander Duyck alexander.h.duyck@intel.com Date: Fri Jul 20 08:08:28 2012 +0000

ixgbe: Have the CPU take ownership of the buffers sooner

This patch makes it so that we will always have ownership of the buffers by the time we get to ixgbe_add_rx_frag. This is necessary as I am planning to add a copy-break to ixgbe_add_rx_frag and in order for that to function correctly we need the CPU to have ownership of the buffer.

Signed-off-by: Alexander Duyck alexander.h.duyck@intel.com Tested-by: Phil Schmitt phillip.j.schmitt@intel.com Signed-off-by: Peter P Waskiewicz Jr peter.p.waskiewicz.jr@intel.com

diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c index 9305e9a..b0020fc 100644 --- a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c +++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c @@ -1458,6 +1458,36 @@ static bool ixgbe_is_non_eop(struct ixgbe_ring *rx_ring, }

/** + * ixgbe_dma_sync_frag - perform DMA sync for first frag of SKB + * @rx_ring: rx descriptor ring packet is being transacted on + * @skb: pointer to current skb being updated + * + * This function provides a basic DMA sync up for the first fragment of an + * skb. The reason for doing this is that the first fragment cannot be + * unmapped until we have reached the end of packet descriptor for a buffer + * chain. + */ +static void ixgbe_dma_sync_frag(struct ixgbe_ring *rx_ring, + struct sk_buff *skb) +{ + /* if the page was released unmap it, else just sync our portion */ + if (unlikely(IXGBE_CB(skb)->page_released)) { + dma_unmap_page(rx_ring->dev, IXGBE_CB(skb)->dma, + ixgbe_rx_pg_size(rx_ring), DMA_FROM_DEVICE); + IXGBE_CB(skb)->page_released = false; + } else { + struct skb_frag_struct *frag = &skb_shinfo(skb)->frags[0]; + + dma_sync_single_range_for_cpu(rx_ring->dev, + IXGBE_CB(skb)->dma, + frag->page_offset, + ixgbe_rx_bufsz(rx_ring), + DMA_FROM_DEVICE); + } + IXGBE_CB(skb)->dma = 0; +} + +/** * ixgbe_cleanup_headers - Correct corrupted or empty headers * @rx_ring: rx descriptor ring packet is being transacted on * @rx_desc: pointer to the EOP Rx descriptor @@ -1484,20 +1514,6 @@ static bool ixgbe_cleanup_headers(struct ixgbe_ring *rx_ring, unsigned char *va; unsigned int pull_len;

- /* if the page was released unmap it, else just sync our portion */ - if (unlikely(IXGBE_CB(skb)->page_released)) { - dma_unmap_page(rx_ring->dev, IXGBE_CB(skb)->dma, - ixgbe_rx_pg_size(rx_ring), DMA_FROM_DEVICE); - IXGBE_CB(skb)->page_released = false; - } else { - dma_sync_single_range_for_cpu(rx_ring->dev, - IXGBE_CB(skb)->dma, - frag->page_offset, - ixgbe_rx_bufsz(rx_ring), - DMA_FROM_DEVICE); - } - IXGBE_CB(skb)->dma = 0; - /* verify that the packet does not have any known errors */ if (unlikely(ixgbe_test_staterr(rx_desc, IXGBE_RXDADV_ERR_FRAME_ERR_MASK) && @@ -1742,8 +1758,16 @@ static bool ixgbe_clean_rx_irq(struct ixgbe_q_vector *q_vector, * after the writeback. Only unmap it when EOP is * reached */ + if (likely(ixgbe_test_staterr(rx_desc, + IXGBE_RXD_STAT_EOP))) + goto dma_sync; + IXGBE_CB(skb)->dma = rx_buffer->dma; } else { + if (ixgbe_test_staterr(rx_desc, IXGBE_RXD_STAT_EOP)) + ixgbe_dma_sync_frag(rx_ring, skb); + +dma_sync: /* we are reusing so sync this buffer for CPU use */ dma_sync_single_range_for_cpu(rx_ring->dev, rx_buffer->dma,